Your method works fine, Mahnmut. I had a quick play as well yesterday. The only thing that needs more attention is the 'gap' between the two half rings. But with a 'line' of fake stones, or vegetation, it should be possible to hide it. I won't be using this, I guess, but it's fun playing with and great to see that for every 'problem' there is a solution. Thanks again, Mahnmut.